123 research outputs found

    Resource Control for Synchronous Cooperative Threads

    Get PDF
    We develop new methods to statically bound the resources needed for the execution of systems of concurrent, interactive threads. Our study is concerned with a \emph{synchronous} model of interaction based on cooperative threads whose execution proceeds in synchronous rounds called instants. Our contribution is a system of compositional static analyses to guarantee that each instant terminates and to bound the size of the values computed by the system as a function of the size of its parameters at the beginning of the instant. Our method generalises an approach designed for first-order functional languages that relies on a combination of standard termination techniques for term rewriting systems and an analysis of the size of the computed values based on the notion of quasi-interpretation. We show that these two methods can be combined to obtain an explicit polynomial bound on the resources needed for the execution of the system during an instant. As a second contribution, we introduce a virtual machine and a related bytecode thus producing a precise description of the resources needed for the execution of a system. In this context, we present a suitable control flow analysis that allows to formulte the static analyses for resource control at byte code level

    Observation of implicit complexity by non confluence

    Get PDF
    We propose to consider non confluence with respect to implicit complexity. We come back to some well known classes of first-order functional program, for which we have a characterization of their intentional properties, namely the class of cons-free programs, the class of programs with an interpretation, and the class of programs with a quasi-interpretation together with a termination proof by the product path ordering. They all correspond to PTIME. We prove that adding non confluence to the rules leads to respectively PTIME, NPTIME and PSPACE. Our thesis is that the separation of the classes is actually a witness of the intentional properties of the initial classes of programs

    Risk analysis and outcome of mediastinal wound and deep mediastinal wound infections with specific emphasis to omental transposition

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>To report our experience, with Deep mediastinal wound infections (DMWI). Emphasis was given to the management of deep infections with omental flaps</p> <p>Methods</p> <p>From February 2000 to October 2007, out of 3896 cardiac surgery patients (prospective data collection) 120 pts (3.02%) developed sternal wound infections. There were 104 males & 16 females; (73.7%) CABG, (13.5%) Valves & (9.32%) CABG and Valve.</p> <p>Results</p> <p>Superficial sternal wound infection detected in 68 patients (1.75%) and fifty-two patients (1.34%) developed DMWI. The incremental risk factors for development of DMWI were: Diabetes (OR = 3.62, CI = 1.2-10.98), Pre Op Creatinine > 200 μmol/l (OR = 3.33, CI = 1.14-9.7) and Prolong ventilation (OR = 4.16, CI = 1.73-9.98). Overall mortality for the DMWI was 9.3% and the specific mortality of the omental flap group was 8.3%. 19% of the "DMWI group", developed complications: hematoma 6%, partial flap loss 3.0%, wound dehiscence 5.3%. Mean Hospital Stay: 59 ± 21.5 days.</p> <p>Conclusion</p> <p>Post cardiac surgery sternal wound complications remain challenging. The role of multidisciplinary approach is fundamental, as is the importance of an aggressive early wound exploration especially for deep sternal infections.</p

    Effects of a home-based intervention on diet and physical activity behaviours for rural adults with or at risk of metabolic syndrome: a randomised controlled trial

    Get PDF
    BACKGROUND: This study aimed to determine whether a home-based 6-month lifestyle intervention program complemented by motivational interviewing could improve diet and physical activity behaviours in 50-69 year olds with or at risk of metabolic syndrome, residing in a disadvantaged rural Western Australian community. METHODS: Participants from the City of Albany and surrounding towns (n?=?401) were recruited into a 6 month randomised controlled trial. They were screened for metabolic syndrome and randomly allocated to intervention (n?=?201) or control group (n?=?200). Baseline and post-test data collection for both groups included a self-report questionnaire which incorporated the Fat and Fibre Barometer and the International Physical Activity Questionnaire Short Form. The intervention group received the program materials at baseline and the control group was waitlisted. Generalised estimating equation models assessed repeated outcome measures over time. RESULTS: A total of 151 (75.1 %) intervention and 159 (79.5 %) control group participants completed post-test and were included in the analysis. After controlling for confounders, the intervention group achieved a marginally significant increase in their metabolic equivalent (MET) minutes of moderate intensity physical activity per week (p?=?0.049), and significantly improved fibre intake (p?&lt;?0.001), fat intake (p?=?0.003), and vegetable serves per day (p?=?0.002) from baseline to post-test relative to the control group. CONCLUSION: A home-based, low-cost intervention with motivational support can effectively improve the physical activity and dietary behaviours of adults aged 50-69 years with or at risk of metabolic syndrome residing in a disadvantaged rural area. TRIAL REGISTRATION: Anzctr.org.au Identifier: ACTRN12614000512628

    Trouble with Bleeding: Risk Factors for Acute Hepatitis C among HIV-Positive Gay Men from Germany—A Case-Control Study

    Get PDF
    OBJECTIVES: To identify risk factors for hepatitis C among HIV-positive men who have sex with men (MSM), focusing on potential sexual, nosocomial, and other non-sexual determinants. BACKGROUND: Outbreaks of hepatitis C virus (HCV) infections among HIV-positive MSM have been reported by clinicians in post-industrialized countries since 2000. The sexual acquisition of HCV by gay men who are HIV positive is not, however, fully understood. METHODS: Between 2006 and 2008, a case-control study was embedded into a behavioural survey of MSM in Germany. Cases were HIV-positive and acutely HCV-co-infected, with no history of injection drug use. HIV-positive MSM without known HCV infection, matched for age group, served as controls. The HCV-serostatus of controls was assessed by serological testing of dried blood specimens. Univariable and multivariable regression analyses were used to identify factors independently associated with HCV-co-infection. RESULTS: 34 cases and 67 controls were included. Sex-associated rectal bleeding, receptive fisting and snorting cocaine/amphetamines, combined with group sex, were independently associated with case status. Among cases, surgical interventions overlapped with sex-associated rectal bleeding. CONCLUSIONS: Sexual practices leading to rectal bleeding, and snorting drugs in settings of increased HCV-prevalence are risk factors for acute hepatitis C. We suggest that sharing snorting equipment as well as sharing sexual partners might be modes of sexual transmission. Condoms and gloves may not provide adequate protection if they are contaminated with blood. Public health interventions for HIV-positive gay men should address the role of blood in sexual risk behaviour. Further research is needed into the interplay of proctosurgery and sex-associated rectal bleeding

    Deep Brain Stimulation of Nucleus Accumbens Region in Alcoholism Affects Reward Processing

    Get PDF
    The influence of bilateral deep brain stimulation (DBS) of the nucleus nucleus (NAcc) on the processing of reward in a gambling paradigm was investigated using H2[15O]-PET (positron emission tomography) in a 38-year-old man treated for severe alcohol addiction. Behavioral data analysis revealed a less risky, more careful choice behavior under active DBS compared to DBS switched off. PET showed win- and loss-related activations in the paracingulate cortex, temporal poles, precuneus and hippocampus under active DBS, brain areas that have been implicated in action monitoring and behavioral control. Except for the temporal pole these activations were not seen when DBS was deactivated. These findings suggest that DBS of the NAcc may act partially by improving behavioral control

    Contrasting Views of the Post-bariatric Surgery Experience between Patients and their Practitioners: a Qualitative Study

    Get PDF
    © 2018, The Author(s). Background: The superiority of obesity surgery for improving medical and weight outcomes in severely obese patients when compared to other weight loss interventions remains undisputed. However, knowledge about the psychological impact of the procedure on patients’ lives is limited. Systematic reviews indicate persisting psychological distress after surgery compared to control groups especially longer term, suggesting the need for postoperative psychological support and assessment. Research literature also infers limited knowledge regarding the postoperative patient experience of obesity surgery. This may form a barrier in health practitioners’ understanding of these patients’ ongoing needs. Methods: Ten patients who had obesity surgery two or more years ago and eight obesity surgery practitioners were recruited within hospital settings and individually interviewed by the researcher to capture their accounts of the postoperative experience. Concordance between the two groups was explored to gauge awareness of patients’ subsequent health needs. Results: Thematic analysis of transcribed interviews elicited a key finding around ‘post-surgical cliffs in patient care’ within a heavily structured service. Participants reported some unmet needs, namely, psychological aftercare to facilitate adjustment following drastic weight loss and excess skin, acceptance of their non-obese self and perceived stigma. The impact of contrasting views of success between patients and practitioners on postoperative care within the service context was highlighted. Conclusions: Obesity surgery is a great weight loss catalyst for severe obesity. However, lack of psychological aftercare may threaten early gains in health outcomes over the longer term. More qualitative and quantitative studies are needed to validate current study results
    • …
    corecore